1. Field of the Invention
The present invention relates to pointing devices for personal computers in general and more particularly to a low profile external pointing device.
2. Discussion of the Related Art
Personal computers have become an integral part to the business and personal activities of a large number of today's individuals. The personal computer has evolved from a desktop box with a CRT monitor largely limited in one fixed location to a state-of-the-art compact notebook with a flat panel display exhibiting processing power and display resolutions only dreamed of a few years ago. Today's notebook computers are small and continue to shrink even as their power continues to expand. These computers utilize operating systems that typically incorporate a graphical user interface (GUI). One of the primary aids for using a GUI is the incorporation of a pointing device to facilitate inputs into the computer. A pointing device permits the users to freely move a “pointer” or cursor around the display screen, to make selections and numerous other functions.
The most common pointing device is a mouse, which typically incorporates a captive ball that is rotated by translating the mouse across a flat surface. An electro-mechanical mechanism in the mouse translates the ball movement into electrical signals that are translated by the computer into movements of the onscreen pointer. The mouse will also incorporate one or more switches or buttons operated by the user's fingers to perform additional functions with respect to the onscreen display. Various configurations of pointing devices have been developed over the years in addition to the mouse such as trackballs, touchpads, joysticks, and touch screens to name a few. Each functions to move the onscreen pointer and has associated therewith one or more input function buttons. However, by far, the most common pointing device associated with a computer is a mouse.
The typical mouse is somewhat voluminous compared to the size of small notebook computers. Manufacturers of notebooks, seeking to retain the mouse's capacities while maintaining the small size of the computer, devised the touchpad, which is a thermal-sensor based device to move the computer's cursor.
While the touchpad does perform the same functions as a mouse, it does so in a way quite different to the manner in which mouse users are accustomed. Use of the touchpad requires repetitive finger movement, leading to a somewhat cumbersome manner of use. In addition, should the user's finger be slightly moist, the performance of the thermal sensors in the pad is degraded. The touchpad is normally located in the center front portion of the keyboard. While this placement accommodates both right- and left-handed users, this compromise position is not particularly comfortable for either to use, since most mouse users, be they right- or left-handed, are accustomed to having the mouse located on a particular side of the keyboard.
The result is that users of notebook computers, who find such pads inefficient, resort to the use of an external mouse even though its volume is cumbersome with relation to the size of the computer. The use of an external mouse somewhat defeats the purpose of the drive towards smaller size and requires the user to carry a separate piece of equipment in additions to the notebook computer. One attempt to alleviate this problem was the development of the mini-mouse. The mini-mouse is smaller than a normal mouse, but is still voluminous compared to the size of the laptop or notebook computer. Further, this external mouse must still be packed separately when traveling. Recently, a flat wireless mouse, the MoGo™, which is storable in the PC Card slot of a notebook computer has been introduced. This is also a touchpad device, but not fully functional.
The use of an external mouse requires the presence of a flat surface near the computer on which to operate the mouse. However, often notebook computers are used on the user's lap or other location where no such useable flat surface may be available. The user must then be content using the cumbersome touchpad. Current mouse designs take on many forms. Some designs attempt to be more ergonomic, since it has been shown that repetitive use of a mouse, which requires grasping it, may lead to physical discomfort, carpal tunnel syndrome, or other repetitive motion injuries.
Thus what is desired is a computer pointing device that is relatively small with respect to a notebook computer.